2) n. state of perfection; state of highest quality; state of prosperity; springtime; childhood; dawn; sunrise; prime number; number that is not divisible by any number except itself and 1 (Mathematics)

(a) prime(b) visibility(c) reach(d) weakness

3) n. system used to place one event in relation to another (such as past vs. present, yesterday vs. today); period; era; hour; rate